Product category:
OEM Pumps
News Release from: Bosch Automotive OE Division | Subject: Auxilliary water pump
Edited by the Engineeringtalk Editorial
Team on 31 March 2005
20 million water pumps and still flowing
Bosch has produced the 20 millionth electrically driven auxiliary water pump at its Buhl plant in Germany, after the the original version 35 years ago.
Bosch has produced the 20 millionth electrically driven auxiliary water pump at its Buhl plant in Germany, after the company went in to the worldwide large-scale production with the original version 35 years ago The pumps are being installed in an increasing number of vehicles due to the quick heating of the car interior during normal driving by redirecting residual engine heat in to the cabin and, even after the ignition key has been removed, the continued ability to cool the engine and also the turbo charger
This article was originally published on Engineeringtalk on 13 Oct 2005 at 8.00am (UK)
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In auxiliary heaters, they pump coolant around the system.
Main water pumps are connected to the drivetrain and provide a reliable circulation of cooling water.
However, the direct coupling to the engine makes the delivery capacity dependent upon engine speed and not necessarily adjusted to the actual requirement.
This is where additional electrically driven water pumps can help.
If the car stops at a traffic light or in traffic congestion in cold weather, for instance, they increase the throughflow to the heat exchanger of the heater said Bosch.
As a result, more heat is available for warming the car interior.
This is of particular benefit in vehicles equipped with modern diesel engines, which dissipate only a little heat due to their efficiency.
The available heat is therefore put to the greatest possible use.
Some vehicles have separate cooling circuits which work with electric auxiliary water pumps.
As these pumps also operate when the engine is switched off, they can keep the cooling or heating circuits functioning in vehicles with start and stop function or hybrid drives which are independent of the combustion engine, added the company.
Bosch said it has continually improved its auxiliary water pumps in terms of function, size and weight.
In 1988, the company started installing solenoid operated couplings, which provided magnetic connection torque transmission from the drive motor to the pump wheel.
The absolute segregation of pump and drive is claimed to guarantee tightness throughout the service life.
In 2001, that was followed up by brushless electric motors, which increased the service life and brought size and weight down even further.
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